Immediate Response Of The Hemoglobin System Of The Goldfish, Carassius Auratus, To Temperature Change
Goldfish acclimated to 3 and 23 °C were characterized by two- and three-component hemoglobin systems, respectively. After acclimation to a diurnally cycling temperature regime (~3 to ~23 °C), specimens sampled at ~23 °C and ~3 °C were identical in terms of hemoglobin system complexity with those held at equivalent constant temperatures. Abrupt transfer of fish acclimated at constant 23 °C to 3 °C, and vice versa, lead to appearance or disappearance of the minor component, G.1, within 3 h. In vitro cooling and warming of whole blood and hemolyzate samples indicated that hemoglobin system modification occurred under cell-free as well as cell-intact conditions. These observations suggest that previously observed quantitative variations in the hemoglobin systems of thermally acclimated teleosts may represent, in part at least, altered aggregation of preexisting subunits rather than de novo hemoglobin synthesis and raise the possibility that teleostean hemoglobin systems may possess a capacity for rapid, adaptative reorganization after environmental temperature variation.